于 2012年04月16日 21:34, Jiri Bohac 写道:
>
> Commit 1716a961 (ipv6: fix problem with expired dst cache) broke
PMTU
> discovery. rt6_update_expires() calls dst_set_expires(), which
only updates
> dst->expires if it has not been set previously (expires
0) or if the new
> expires is earlier than the current dst->expires.
>
> rt6_update_expires() needs to zero rt->dst.expires, otherwise it will contain
> ivalid data left over from rt->dst.from and will confuse dst_set_expires().
>
> Signed-off-by: Jiri Bohac <jbohac@suse.cz>
>
> diff –git a/include/net/ip6_fib.h b/include/net/ip6_fib.h
> index ad4126f..68c1f94 100644
> — a/include/net/ip6_fib.h
> +++ b/include/net/ip6_fib.h
> @@ -143,8 +143,13 @@ static inline void rt6_set_expires(struct rt6_info *rt, unsigned long expires)
>
> static inline void rt6_update_expires(struct rt6_info *rt, int timeout)
> {
> - if (!(rt->rt6i_flags & RTF_EXPIRES) && rt->dst.from)
> - dst_release(rt->dst.from);
> + if (!(rt->rt6i_flags & RTF_EXPIRES)) {
> + if (rt->dst.from)
> + dst_release(rt->dst.from);
> + /* dst_set_expires relies on expires 0
> + if it has not been set previously */
> + rt->dst.expires = 0;
> + }
>
> dst_set_expires(&rt->dst, timeout);
> rt->rt6i_flags |= RTF_EXPIRES;
>
looks good to me, thanks.